From 61a851845546300cc2f5ee9f3dd6761c9ecd093e Mon Sep 17 00:00:00 2001 From: Jie Hu Date: Wed, 16 Dec 2015 18:52:19 +0800 Subject: ESCALATOR-31 Adjusting documentation JIRA: ESCALATOR-31 Change-Id: I0b83511a542982f07c2ab9d60517f4b5f357569b Signed-off-by: Jie Hu --- docs/requirements/102-Terminologies.rst | 129 ++++++++++++++++++++++++++++++++ 1 file changed, 129 insertions(+) create mode 100644 docs/requirements/102-Terminologies.rst (limited to 'docs/requirements/102-Terminologies.rst') diff --git a/docs/requirements/102-Terminologies.rst b/docs/requirements/102-Terminologies.rst new file mode 100644 index 0000000..221196b --- /dev/null +++ b/docs/requirements/102-Terminologies.rst @@ -0,0 +1,129 @@ +=========== +Terminology +=========== + +Terminologies +============= + +Operator + The term refers to network service providers and Virtual Network + Function (VNF) providers. + +End-User + The term refers to a subscriber of the Operator's services. + +Network Service + The term refers to a service provided by an Operator to its + end-users using a set of (virtualized) Network Functions + +Infrastructure Services + The term refers to services provided by the NFV Infrastructure to the VNFs + as required by the Management & Orchestration functions and especially the VIM. + I.e. these are the virtual resources as perceived by the VNFs. + +Smooth Upgrade + The term refers to an upgrade that results in no service outage + for the end-users. + +Rolling Upgrade + The term refers to an upgrade strategy, which upgrades a node or a subset + of nodes at a time in a wave style rolling through the data centre. It + is a popular upgrade strategy to maintain service availability. + +Parallel Universe Upgrade + The term refers to an upgrade strategy, which creates and deploys + a new universe - a system with the new configuration - while the old + system continues running. The state of the old system is transferred + to the new system after sufficient testing of the new system. + +Infrastructure Resource Model + The term refers to the representation of infrastructure resources, + namely: the physical resources, the virtualization + facility resources and the virtual resources. + +Physical Resource + The term refers to a piece of hardware in the NFV infrastructure that may + also include firmware enabling this piece of hardware. + +Virtual Resource + The term refers to a resource, which is provided as services built on top + of the physical resources via the virtualization facilities; in particular, + virtual resources are the resources on which VNFs are deployed. Examples of + virtual resources are: VMs, virtual switches, virtual routers, virtual disks. + +Visualization Facility + The term refers to a resource that enables the creation + of virtual environments on top of the physical resources, e.g. + hypervisor, OpenStack, etc. + +Upgrade Campaign + The term refers to a choreography that describes how the upgrade should + be performed in terms of its targets (i.e. upgrade objects), the + steps/actions required of upgrading each, and the coordination of these + steps so that service availability can be maintained. It is an input to an + upgrade tool (Escalator) to carry out the upgrade. + +Upgrade Duration + The duration of an upgrade characterized by the time elapsed between its + initiation and its completion. E.g. from the moment the execution of an + upgrade campaign has started until it has been committed. Depending on + the upgrade strategy, the state of the configuration and the upgrade target + some parts of the system may be in a more vulnerable state with respect to + service availbility. + +Outage + The period of time during which a given service is not provided is referred + as the outage of that given service. If a subsystem or the entire system + does not provide any service, it is the outage of the given subsystem or the + system. Smooth upgrade means upgrade with no outage for the user plane, i.e. + no VNF should experience service outage. + +Rollback + The term refers to a failure handling strategy that reverts the changes + done by a potentially failed upgrade execution one by one in a reverse order. + I.e. it is like undoing the changes done by the upgrade. + +Backup + The term refers to data persisted to a storage, so that it can be used to + restore the system or a given part of it in the same state as it was when the + backup was created assuming a cold restart. Changes made to the system from + the moment the backup was created till the moment it is used to restore the + (sub)system are lost in the restoration process. + +Restore + The term refers to a failure handling strategy that reverts the changes + done, for example, by an upgrade by restoring the system from some backup + data. This results in the loss of any change and data persisted after the + backup was been taken. To recover those additional measures need to be taken + if necessary (e.g. rollforward). + +Rollforward + The term refers to a failure handling strategy applied after a restore + (from a backup) opertaion to recover any loss of data persisted between + the time the backup has been taken and the moment it is restored. Rollforward + requires that data that needs to survive the restore operation is logged at + a location not impacted by the restore so that it can be re-applied to the + system after its restoration from the backup. + +Downgrade + The term refers to an upgrade in which an earlier version of the software + is restored through the upgrade procedure. A system can be downgraded to any + earlier version and the compatibility of the versions will determine the + applicable upgrade strategies and whether service outage can be avoided. + In particular any data conversion needs special attention. + +Abbreviations +============= + +NFVI + The term is an abbreviation for Network Function Virtualization + Infrastructure; sometimes it is also referred as data plane in this + document. The NFVI provides the virtual resources to the virtual + network functions under the control of the VIM. + +VIM + The term is an abbreviation for Virtual Infrastructure Manager; + sometimes it is also referred as control plane in this document. + The VIM controls and manages the NFVI compute, network and storage + resources to provide the required virtual resources to the VNFs. + -- cgit 1.2.3-korg